Dye bath and process of dyeing



Patented May-12, 1931 1 8 8.

' UNITED STATE s PATENT"- OFFICE I Am NATHANIEL KosAx, or EVERETT,

RICHARD G. KNOWLAND, or WOLLASTON,

pose, the goods are stituents that have no MASSACHUSETTS, ASSIGNORS TO NASHUA MANUFACTURING COMPANY, OF N ASHUA, NEW HAMPSHIRE, A CORPORATION OF NEW HAMPSHIRE DYE BATH AND PROCESS OF DYEING .No Drawing.

This invention relates to vat dye baths and processes of vat dyeing fabrics, yarn, or. fibre,

all of which will be hereinafter included in l reduced condition and in an alkaline solution in order to make the dye adhere to the fibre of the goods. In a typical process the dye is reduced by sodium hyposulphite and is applied to the goods in acaustic soda solutlon. After the fabric has been run through the dye bath it is, in a typical process, washed with water, the dye is then oxidized, an agent such as sodium perborate or potassium b1- chromate being commonly used for this puragailrwashed, given the usual soaping treatment and then glven a final washing and drying. 1

' The present invention aims to improve vat dye baths and-processes of vat dyeing with a view to reducing the handling of the goods and the treatments re uired after the dyeing operation per se has eenperformed.

We have discovered that this resultcan be realizedby substituting for thecaustic soda ordinarily used in preparing the dye bath, an alkaline material which will break up upon the subsequent drying of the goods into conharmful efiect on the goods and which preferably are volatile in nature so that they can be driven out of the goods during the dryingjstep. The quarternary ammonium bases as tetramethylammonium hydroxide or Ttetramethylammomum hydroxide are particularly sat sfactory for this purpose.

The vat dye bath can be prepared 1n the usual way, the dye being reduced by sodium hydrosulphite or any other'suitable reducing agent in a solution which isglven the esired degree of alkalinity by the addition thereto of a suitable quantity of either of the ammonium bases above mentioned. A for mula suitable for laboratory purposes is as follows:

0.4 gms. indanthrene blue GCD (color 1ndex number 1113).

1.6 gms. sodium hydrosulphite. 290,0 cc. tetramethylammonium Application filed March 12,

practice being required because hydroxide 1928. Serial N0. 261,178.

solution containing 15.7 gms. per whole made up to 600 c.

understood however, that the proportions of the ingredients may be varied in-accordance with the nature of the dye used, the results desired, and other practical considerations, the foregoing pfgrmula serving simply as an example. The dyeing operation may be performed in the usual manner, no change in the usual of the use of quarternary ammonium bases. As the fab-- ric emerges from the dye bath. it is run between rollers to squeeze out the surplus color and is then dried. Ordinarily the drying operation is performed by running the fabric over a so-called can dryer]? It is obvious that the goods can be washed if desired but -washing is not necessary. They can also be treated with oxidizing agents if desired, and in some cases such treatment is preferable. Usually, however, an entirely satisfactory oxidation of the dye takes place during the drg ing operation.

- he step of dryingthe goods ordinarily is conducted under a moderate heat, a temperature of at least 60 C. being maintained, and

such a temperature issufficient to break up the quarternary ammonium base into volatile constituents which are driven out of the goods. If tetramethylammonium hydroxide that the invention. may be practiced in a variety of ways without departing from the spirit or scope thereof.

Having thus described our invention, what we desire to claim as new is:

1. That improvement in methods of vat liter, the

'is used it decomposes upon heating into dyeing fabrics which consists in dyeing the goods in a dye bath made alkaline by the addition of a suitable quantity of a quarternary ammonium base, and subsequently, whilethe goods still contain a considerable percentage of said bath, drying the goods at g temperature serving to decompose said ase.

2. That improvement in methods of vat dyeing fabrics which consists in dyeing the goods in a dye bath made alkaline by the addition of a suitable quantity of a quarternary ammonium base, squeezing out the surplus dye bath, and subsequently drying the goods at -a temperature serving to decompose said base.

3. That improvement in methods of vat dyeing fabrics which consists in dyeing the goods in a bath containing a solution of the dye, a reducing agent, and an alkaline material which will break down into volatile constituents upon heating and subsequently drying the fabric at a temperature sufficient to decompose said alkaline material.

4. That improvement in methods of vat dyeing fabrics which consists in dyeing the goods in a bath containing a solution of the dye, a reducing agent, and a quarternary ammonium base.

5. That' improvement in methods of vat dyeing fabrics which consists in dyeing the goods in a bath containing a solution of the dye, a reducing agent, and a quarternary ammonium base, and subsequently drying the fabric under conditions which decompose said base.

6. A vat dye bath containing suitable pro portions of a vat dye, a reducing agent, and

an alkali adapted to break down under moderate heat into constituents harmless to the goods.

7. A vat dye bath containing suitable prov portionsof a vat dye, a reducing agent, and

an alkali, the alkali being adapted to decompose into volatile constituents when heated to moderate temperatures.

8. A vat dye bath containing suitable proportions of a dye, a reducing agent, and a quarternary ammonium base.

In testimony whereof We have hereunto signed our names to this specification.

RICHARD G. KNOWLAND. NATHANIEL KOSAK.

CERTIFICATE or CORRECTION.

Patent No. 1,805,098. Granted May 12, 1931, to

RICHARD c. KNOWLAND ET AL.

It is hereby certified that error appears in the printed specification of the above nurnbered patent requiring correction as follows: Page 1, line 35, for the misspelled word "tetramethylammonium" read tetraethylammonium; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 7th day of July, A. D. 1931.

. M. J. Moore, (Seal) Acting Commissioner of Patents. 

